Microfabrication by lithography using a photoresist composition has been carried out in manufacture of semiconductor devices. The microfabrication is a processing method including forming a thin film of a photoresist composition on a substrate to be processed such as a silicon wafer, irradiating the formed thin film with active light through a mask pattern formed by drawing a semiconductor device pattern on the formed thin film, developing the irradiated thin film, and etching the substrate to be processed such as a silicon wafer using the obtained photoresist pattern as a protecting film. In recent years, however, semiconductor devices have been further integrated, and the active light to be used has tended to have a shorter wavelength from a KrF excimer laser (248 nm) to an ArF excimer laser (193 nm). This raises serious problems of the effects of diffused reflection of active light from the substrate and standing wave. Consequently, a method for providing a bottom anti-reflective coating (BARC) between a photoresist and a substrate to be processed has been widely studied. For example, a composition for forming a photosensitive resist underlayer film containing a polymer including an acrylamide structure has been described (refer to Patent Document 1).
A composition for forming a resist underlayer film containing a polymer having a unit structure of hydroxyacrylamide has been described (refer to Patent Document 2).
A composition for forming an anti-reflective coating containing a polymer including a unit structure of the hydroxyalkylene methacrylamide and a unit structure of aromatic alkylene methacrylate has been described (refer to Patent Document 3).
In future, when finer resist pattern formation will progress, the problem of resolution and the problem of collapse of the resist pattern after development will arise and thus a thinner resist film formation will be desired. Since the sufficient resist pattern thickness required for substrate processing is difficult to obtain, a process in which not only the resist pattern but also the resist underlayer film formed between the resist and the semiconductor substrate to be processed has the function as a mask is required. As the resist underlayer film for such a process, a resist underlayer film for lithography having the selectivity of a dry etching rate close to that of the resist, a resist underlayer film for lithography having the selectivity of dry etching rate smaller than that of the resist, or a resist underlayer film for lithography having the selectivity of dry etching rate smaller than that of the semiconductor substrate, which is different from conventional resist underlayer films having high etch rate properties (fast etching rate), has been required.
With formation of a finer pattern, a patterning method of reversing the pattern has been disclosed (refer to Patent Documents 1 and 2). A method for producing electronic devices has been disclosed (refer to Patent Document 3). The method includes (a) sequentially forming an anti-reflective coating and a resist on a film to be processed as a patterning target, (b) forming an opening in a predetermined region of the resist by an exposure process and a development process to remove the anti-reflective coating in the opening, (c) applying a predetermined insulating film material on the resist in which the opening is formed and baking the applied insulating film material to form an application type insulating film, (d) removing the application type insulating film existing except within the opening, (e) forming a first mask pattern formed of the application type insulating film in the predetermined region by removing the resist and the anti-reflective coating, and (f) patterning the film to be processed by etching the film to be processed using the first mask as a mask.